Modern process installations are used to provide and/or produce a variety of products and materials used every day. Examples of such process installations include petroleum refining installations, pharmaceutical production installations, chemical processing installations, pulp and other processing installations. In such installations, a process control and measurement network may include thousands or even of tens of thousands of various field devices communicating with a control room, and sometimes with one another, to control the process. Given that malfunctions in a given field device could cause the process to go out of control, the physical characteristics, and electrical communication of field devices is generally subject to stringent specifications.
Traditionally, field devices in a given process installation have generally been able to communicate over a process control loop or segment with a control room and/or other field devices via wired connections. An example of a wired process communication protocol is known as the Highway Addressable Remote Transducer (HART®) protocol. HART® communication is one of the primary communication protocols used in the process industries. Recently, it has become possible, and potentially desirable in some cases, to permit process installations access to the Internet. While such a feature provides the ability to interact with the process installation from virtually any connected computer around the globe, it also provides the potential for a malicious entity, such as a hacker, to attempt to influence the process installation without travelling to the physical location of the process installation.
Another recent development with respect to process installations is utilization of wireless communication. Such wireless communication simplifies process installations in that it is no longer required to provide long runs of wires to the various field devices. Moreover, one such wireless protocol, WirelessHART (IEC 62591), expands upon the traditional HART® protocol and provides vastly increased data transfer rates. For example, WirelessHART supports communication up to 250 Kbps. Relevant portions of the Wireless HART® Specification include: HCF_Spec 13, revision 7.0; HART Specification 65—Wireless Physical Layer Specification; HART Specification 75—TDMA Data Link Layer Specification (TDMA refers to Time Division Multiple Access); HART Specification 85—Network Management Specification; HART Specification 155—Wireless Command Specification; and HART Specification 290—Wireless Devices Specification. While wireless communication provides a number of advantages for process installations, it also allows for devices in the physical proximity of the process installation to potentially engage and affect the wireless communication network.
Given the recent connectivity of process installations, it is now vitally important that process communication be protected from intrusion and activities of malicious entities. This applies for process installations that may be connected to the Internet, process installations that employ wireless process communication, or both. Accordingly, providing a process installation with the ability to detect and prevent intrusion upon a process communication loop would further help secure the various process installations that rely upon process communication.